Original title: Valve-in-Valve Implantation of Medtronic CoreValve Prosthesis in Patients with Failing Bioprosthetic Aortic Valves. Reference: Axel Linke el al. Circ Cardiovasc Interv. 2012;5:689-697.
This study evaluates the safety, feasibility and results of Core Valve implants on patients with bioprostheses dysfunctional by stenosis, insufficiency or a combination of both.
Biological prostheses are preferred over mechanical ones for patients older than 65 years since no anticoagulation requirements are needed. The problem is that they can deteriorate and eventually lose their function over time. These patients have a high morbidity and mortality rate if they are re-operated. .
27 consecutive patients were treated, symptomatically discarded because of high-risk surgery, (EuroSCORE log 31.3 ± 16.5). Femoral access was under local anesthesia. The events and results of the procedure were analyzed according to the definitions of the Valvular Academic Research Consortium (VARC).
A Core Valve was implanted successfully in all patients. One suffered an embolization but was corrected with a second valve while two died after procedure.
Gradients decreased by 83%, (peak gradient of 58 ± 21 to 12 ± 8 mmHg and mid gradient of 42 ± 15 to 10 ± 8 mmHg). 3 patients stayed on grade 2 aortic regurgitation diagnosis. According to VARC definitions, success was not achieved in 11 of the 27 patients, (44%). All symptoms improved, even those in which the mid-gradient remained > 20 mmHg. 30-day mortality was 7.4% and at long follow-up, (421 ± 198 days), it was 15%. One patient, (2.7%), required a permanent pacemaker.
Conclusions:
The implantation of a Core Valve, (Medtronic), for femoral access under local anesthesia for patients with dysfunctional bioprostheses is safe and feasible in this high-risk cohort.
Editorial comment:
Although more than 15,000 Core Valve, (Medtronic), have been implanted worldwide, experience in treating dysfunctional bioprostheses is limited. This is the largest series of valve-in-valve Valve Core followed for more than one year. It is noteworthy that the gradient post implant, although significantly improved compared to baseline, was below the outcome in patients with native valve. This could be due to a mismatch between the patient and the original prosthesis. It also draws attention to the low need for a permanent pacemaker post implantation, (only 2.7%). It is possible that fibrosis due to previous surgery somehow protects the drive system. Patients with a dysfunctional biological valve can be treated with the Core Valve implantation with good long-term results and a clear clinical improvement, although we should be less demanding regarding residual gradients